Rail-joint.



A. AMBERT.

RAIL JOINT.

APPLICATION FILED JAN. s, 1908.

921 ,577. Patented May 11, 1909.

ALEXANDRE AMBERT, OF LYON, FRANCE.

RAIL-JOINT.

Specification of Letters Patent.

Patented May 11, 1909.

Application filed January 3, 1908. Serial No. 409,104.

To all whom it may concern:

Be it known that I, ALEXANDRE AMBERT, citizen of the French Republic, residing at Lyon, Department of the Rhone, in France, have invented certain new and useful Improvements in Rail-Joints, of which the fol lowing is a specification.

The invention has for its object improvements in the rail-joints of the kind in which the rails are fixed to the sleepers by means of bonds, tightened by wedges driven in at high pressure see for example the method of mounting described in the Patents Nos. 728,652 and 771,692.

The principal improvement consists in giving a preliminary polish to the tightening wedges applied. on the upper part of the bottom of the bond and the under part of the foot of the rail.

When the parts are used in a rough form as they leave the rolling mills or presses, the mounting necessitates the use of great power owing to the friction between the rough surfaces. If, on the other hand, care be taken to polish the faces of the wedges, the sole of the foot and the upper horizontal face of the bond, the same tightening power may be produced on the bond with a far smaller thrust upon the wedges or with an equal thrust, a far higher tightening power without deformation of the wedges. Thus in the case in which the inclination of the wedges is 1 100, the force F of the thrust to be exerted upon the head of the wedge along its axis is related to the clamping force P exerted by the jaws of the bond, by the formula P 1.8 X F in the case of unpolished surfaces and P 4.75 F in the case of polished surfaces. For example, for a thrust P of 30 tons, we obtain a clamping effect of 142 tons in the case of polished surfaces, while a thrust of 80 tons is required for obtaining the same tightening effect with rough surfaces. This polishing of the bonds and wedges permits of effecting the mounting by driving in the wedges with a sledge hammer and of dispensing with the employment of screw presses. For the same reasons, detachment of the wedge necessitates a far smaller expenditure of power when the faces of the wedges and bonds are polished; in addition to this, as the mounting has been effected Without gripping or binding, the metal is not torn away during the detachment and the wedges may be again employed.

In electric lines the polishing of the contact surfaces presents the advantage of insuring complete conductivity of the rail bonds; with bonds of this kind it is unnecessary to use copper connections for uniting two adjacent rails electrically. When metal sleepers are employed it is also possible by polishing the bond and the sleeper suitably to connect the two rows of rails electrically at intervals. In electrical lines it is advantageous to facilitate mounting by lubricating the wedges by means of graphite, which is a conducting substance. Nevertheless, the polishing of the various parts facilitates their creeping during movements of expansion, even when no loosening of the bonds takes place, so that the track might present a tendency to slip little by little owing to the phenomenon known as creeping. I

The manner in which the invention is carried out in practice is illustrated in the accompanying drawings in which:

Fi ure 1 is a cross sectional view showing a rai joint constructed in accordance with the present invention. Fig. 2 is a side elevation thereof. Figs. 3 and 4 are cross sectional views illustrating other forms of means to limit the longitudinal creeping of the rails.

A rail joint constructed in accordance with the present invention comprises, in its general organization, a rail bond, as 1, having overhanging clamp noses 14, which strongly grip the flanges of the rail at the oints 10 and 11. Between the base of the 0nd and the rail cooperating relatively oppositely inclined wedges as 12 and 13 are inserted and such wedges serve to maintain the clamping engagement of the noses 14 upon the rail flanges.

One method of limiting the displacements due to expansion in each length of the track consists in the employment of pins 4 (Fig. 3), passed through holes 5 formec in the web of the rail and engaged in notches 6 formed on the top of the jaws of the bond. Or finally screw threaded or plain pins 7 (Fig. 4) passing through the rail in holes 8 and the jaws of the bond in holes 9 may be employed; these jaws then present a special form. The object of these pinning devices is to prevent creeping of the rails by regulating the expansion of each bond in cases where the ex ansion of the joints is indispensable; in 'act, owing to the polishing, all the joints lend themselves to expansion.

The rails thus pinned and bonded are capable of displacement in the direction of their length, but this will not prejudicially affect the electrical contact, as the contacting surfaces are more than sufficient for .the passage of the current and the spring action ex- 5 erted by the bond upon the foot gives a considerable clamping action to the joint which insures the necessary conductivity, in spite of the slipping of the rails in the bond. 7

In the manufacture the nose 14 of the jaw of the bond is depressed slightly, in such a manner that between this nose and the bottom of the bond the interval left is less than the thickness of the assemblage formed by the rail foot and the wedges when driven 15 right home; this reduction of the aperture of the bond is termed the pinching. At the s, beginnin of the laying operation, the jaw of the bonc bears upon the foot only by the nose 14 but under the influence of the thrust upon the wedges the jaws open until the pinching is eliminated; the jaws then exert at the points 10 and 11 (Fig. l) a vigorous action upon the top of the rail foot while the bottom of the bond is as vigorously applied beneath the wedges.

Having now particularly described and ascertained the nature of my said invention, and in what manner the same is to be performed, I'declare that what I claim is: 1. In a rail joint the combination with a pair of meeting rail sections of a bond straddling the rail sections and contacting with the base flanges thereof, a pair of cooperating wedges interposed between the under faces of the rail sections and the upper surface of the bond, said wedges being longitudinally disposed with res ect to the rail sections and to the bond and eing tightened by axial inward movement, and means for limiting the creeping of the rail sections, said wedges and said bonds having polished contacting faces.

2. In a rail joint the combination with a pair of meeting rail sections of a bond straddling the rail sections and contacting with the base flanges thereof, a pair of cooperating wedges separable from the bond and interposed between the upper face of the bottom portion thereof and the under faces of the rail sections, the said rail sections and said bond having polished contacting surfaces and means for limiting the creeping of the rail sections.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

ALEXANDRE AMBEBT.

l/Vitnesses:

THos. N. BROWNE, MARIN VAoHoRY. 

